In 3D mesh coding, geometry data is usually compressed by spatial tree decomposition based approaches, e.g. Octree based methods. Besides the support of progressive coding, they achieve a considerable compression gain. In an Octree based method, a coder recursively subdivides the smallest axis-aligned bounding box of given 3D model into eight children cells. A cell is recursively subdivided until each nonempty cell is small enough to contain only one vertex and enable a sufficiently precise reconstruction of the vertex position. For each cell subdivision, whether or not each child cell is empty is signified by a symbol. A symbol sequence describing the Octree, called the traversal symbol sequences is generated by first traversing and collecting the symbols representing the subdivision of the nodes. Then an entropy codec is utilized to compress that symbol sequence.